Interpretive Summary: Lady beetles (a. k. a., ladybugs or ladybird beetles) are common insects in gardens and other places where plants are grown. Those that eat aphids ("plant lice") are well-known. Less well-known are ones that eat spider mites. In this paper, we review applied aspects of the life history of a tiny, black lady beetle, Stethorus punctillum. It is produced on a commercial scale by a few companies to help growers control spider mites (such as the two-spotted spider mite) on plants in greenhouses, interiorscapes, nurseries, and orchards. USDA-ARS researchers at the National Biological Control Laboratory are collaborating with one company to discover ways of producing S. punctillum at lower cost.

Technical Abstract:
We review the ecology, life history, and effectiveness of Stethorus punctillum, a tiny, black-colored lady beetle of European origin. This lady beetle is a specialist predator of pest mites in greenhouses, interiorscapes, nurseries, and orchards. It attacks pest mites including the two-spotted spider mite (Tetranychus urticae), European red mite (Panonychus ulmi), spruce spider mite (Oligonychus ununguis), and the southern red mite (Oligonychus ilicis). S. punctillum is compatible with the use of predatory mites in IPM systems to control spider mites on peppers and cucumbers in greenhouses. S. punctillum is compatible with the use of fenbutatin, which is an organotin miticide, for added control of spider mites in “hot spots” at normal field rates. In laboratory or greenhouse cultures, S. punctillum females produce an average of 160 eggs over a lifespan of approximately 60 days, under continuous rearing at room temperature. There is an expanding market for S. punctillum and other predators to control spider mites as alternatives to chemical pesticides. There is a great need for a more cost-effective system of rearing S. punctillum at a commercial scale. USDA-ARS researchers are collaborating with biocontrol producers to discover ways of producing this predator at lower cost.